179566 research outputs found
Sort by
Magnesium in the Critically Ill Patient
Get PDFMagnesium is an essential electrolyte, being the second most abundant intracellular cation and having many physiologic functions in the body.1 It is an essential cofactor for many enzymes, including Na-K-ATPase, calcium ATPase, cyclases (eg, adenylyl cyclase, guanylyl cyclase), protein kinases, DNA and RNA polymerases, and is vital for protein and DNA synthesis, carbohydrate metabolism, cell signaling, immune modulation, and coagulation. Because of its role as a calcium antagonist, magnesium also alters electrophysiological properties of cells and hence influences membrane resting potentials, neurotransmitter release, cell excitability, and muscle contractility.4 Magnesium-mediated inhibition of calcium ion currents in vascular smooth muscle has vasodilatory effects because of L-type calcium channel inhibition (and hence decreased activity of calmodulin-dependent myosin light chain kinase), modulation of intracellular cell signaling, and activation of the sarcoplasmic/endoplasmic reticular Ca2+ATPase resulting in calcium sequestration
Process Modelling, Simulation and Technoeconomic Evaluation of Batch vs. Continuous Pharmaceutical Manufacturing (CPM) of Cephalexin
No full textCost-effective antibiotics production is essential in the fight against antimicrobial resistance, since pharmaceutical companies must frequently abandon their antibiotics research due to: (i) high research and development (R&D) costs, (ii) increasingly stringent environmental regulations, and (iii) government initiatives aimed at curbing antimicrobial resistance by restricting use of new antibiotic products. Consequently, in-silico process design can be effectively employed to reduce the manufacturing cost of new and existing antibiotics whilst simultaneously accelerating their development and improving their affordability. The present paper examines how process modelling and technoeconomic evaluation can be used to guide the design of fully aqueous and aqueous two-phase system (ATPS) manufacturing platforms for the production of cephalexin, a generic cephalosporin antibiotic. Moreover, detailed comparisons of batch vs. continuous pharmaceutical manufacturing (CPM) for the ATPS protocol illustrate key benefits.</p
Experimental and Numerical Investigation of Micro/Mini Channel Flow Boiling with a Self-Rewetting Fluid at different Flow Inclinations
No full textFlow boiling of a self-rewetting fluid (SRF) in high aspect ratio microchannels was investigated experimentally at various applied heat fluxes, and supported with numerical simulations to provide small scale insight into the thin film liquid regions. A 5% v/v 1-butanol-water mixture was used as the SRF and was compared to pure water. The microchannel had an aspect ratio of 20 (6 mm width by 0.3 mm height) and a length of 70 mm and received one-sided heating. Experimental work considered sub-cooled liquid inlet conditions for five channel inclination angles ranging from -90° (downward flow) to 90° (upward flow) at mass fluxes of 10, 15 and 25 kg/m2s. It was observed that the flow inclination severely affected the vapour liquid distribution in the channel and the heat transfer performance. Upward flow had better heat transfer performances than downward flow. Compared to water, the SRF had a similar heat transfer performance for horizontal flow, but outperformed the water for downward flow to such an extent that the SRF exhibited a steady robust boiling mechanism while water almost instantly resulted in severe dry-out at the top (inlet) of the channel. Further insight was obtained via a series of two-dimensional numerical simulation at a mass flux of 15 kg/m2s. It was found and shown via velocity vectors that the unique surface tension properties of the SRF meant that the surrounding fluid was drawn into the heated region, as explained by the Marangoni effect, allowing for a continually wetted surface, and thus enables continued boiling to occur. Numerically it was found, compared to the water, that for the SRF the surrounding fluid flow resulted in reduced bubble growth rates, as well as thicker liquid film layers between the bubble and heated wall
RESTART trial main results dataset
No full textAnalysis dataset used for the RESTART main results and imaging sub-study results papers in 2019Salman, Rustam Al-Shahi; Stephen, Jacqueline; Drever, Jonathan. (2021). RESTART trial main results dataset, 2013-2018 [dataset]. University of Edinburgh. Deanery of Clinical Sciences. Centre for Clinical Brain Sciences. https://doi.org/10.7488/ds/3097
A relation between the Dirichlet and the Regularity problem for Parabolic equations
No full textWe study the relationship between the Dirichlet and Regularity problem for parabolic operators of the form L=div(A∇⋅)−∂ t on cylindrical domains Ω=O×R, where the base O⊂R n is a uniform domain with n−1 Ahlfors regular boundary (and for one result a Lipschitz domain) in the spatial variables. In the paper we answer the question when the solvability of the L p Regularity problem for L (denoted by (RL) p) can be deduced from the solvability of the L p ′ Dirichlet problem for the adjoint operator L ⁎ (denoted (DL⁎) p ′ ). We show that this holds if for at least one q∈(1,∞) the problem (RL) q is solvable. That is, we establish a duality/dichotomy result: Dirichlet solvability implies Regularity solvability in the dual L p range, or the Regularity problem is not solvable in any L p. Results like these were only known in the elliptic settings (Kenig-Pipher (1993) and Shen (2006)) but are new for parabolic PDEs. Our result is one of the key components needed for the recent advancement of Dindoš, Li and Pipher in understanding solvability of the Regularity problem for operators whose coefficients satisfy certain natural Carleson condition (called also DKP-condition in the elliptic case).</p
Stochastic modelling of burden of livestock diseases on domestic ruminants in Ethiopia
No full textThis study, carried out in 2022-2023, quantified the financial burden of disease in cattle, sheep and goats in Ethiopia for the year 2021 using the animal health loss envelope (AHLE) metric. The AHLE measures all cause disease burden, avoidable and non-avoidable, as the difference in the financial performance of a livestock production system (e.g., gross margin) comparing a scenario where animals are in an ideal state of health to the current situation. A stochastic dynamic population model (DPM) was employed to calculate the gross margin for an average farm and for the national herd under these current and ideal health scenarios. Data for parametrizing the DPM were derived from secondary sources and expert elicitation. The stochastic DPM was simulated for 10,000 iterations and results are reported as means with 95 % percentile intervals (PI). The annual AHLE per average farm was estimated at USD 1209 (95 %PI:392-2470) in cattle, USD 158 (95 %PI:66-292) in sheep and USD 416 (95 %PI:136-847) in goats. At national level, the annual AHLE in ruminants was USD 18.39 billion with USD 15.42 billion (95 % PI:12.70-18.57) in cattle, USD 1.04 billion (95 % PI:0.84-1.30) in sheep, and USD 1.93 billion (95 % PI:1.64-2.25) in goats. Morbidity losses constituted the largest component of the AHLE, exceeding 50 % across all species, while animal health expenditure represented the smallest component, accounting for less than 2 % of AHLE in all species. This high disease burden, with minimal contribution from animal health expenditure, indicates significant opportunity for improvement through investment in animal health.</p
Localised variants of multilinear restriction
Get PDFWe revisit certain localised variants of the Bennett-Carbery-Tao multilinear restriction theorem, recently proved by Bejenaru. We give a new proof of Bejenaru's theorem, relating the estimates to the theory of Kakeya-Brascamp-Lieb inequalities. Moreover, the new proof allows for a substantial generalisation, exploiting the full power of the Kakeya-Brascamp-Lieb theory
Boost of trace methane photo-oxidation in the presence of water vapor via the interfacial hydrophobic effect
No full textThe study of water resistance of methane photo-oxidation catalysts is important and challenging for the removal of methane from the atmosphere. Herein, we investigate the mechanistic role of water in the photocatalytic oxidation of trace methane on ZnO decorated with various metal (Cu, Pt). We found that suppressing water dissociation at active sites mitigates hydroxyl-induced catalyst poisoning. Critical insight reveals that photo-generated holes (h+) mediate the conversion of passivating hydroxyl groups (OH*) into reactive hydroxyl radicals (•OH), simultaneously liberating active sites and promoting the reaction. In addition, temperature-dependent experiments revealed that increasing the temperature from 20 to 80 °C enhanced the methane conversion by approximately 4-fold, proving that partial desorption of water molecules from the catalyst surface releases active sites. The experimental results show that 0.5 % Pt/ZnO is about 2-fold more water resistant than 0.5 % Cu/ZnO. These findings provide valuable experience and guidance for both mechanistic understanding of water-mediated methane photooxidation and rational design of high-performance catalysts.</p
Learning in the experiential continuum:A philosophically informed view of professional socialisation
No full textProfessional socialisation is a concept that encapsulates the multifactorial and complex learning process through which a person becomes a member of a profession. In the field of nursing, existing literature on professional socialisation has primarily focused on describing students' key learning experiences during university education. This tendency has been crucial to identifying and characterising the relevance of students' interactions with faculty, patients, and peers and their engagement with the occupational culture and institutional norms, among other learning experiences. However, few studies have taken a step back to elaborate on the theoretical underpinnings of students' socialisation, such as the underlying approach to learning or, more fundamentally, what is understood by human experience. We argue that this omission has precluded a more comprehensive view of professional socialisation. Addressing this gap, in this article, we integrate philosophy to develop a framework that intertwines the concepts of experience, learning, and socialisation. In so doing, we propose that learning occurs within an experiential continuum. Ultimately, this framework operates as theoretical scaffolding that offers a deeper understanding of students' learning during professional socialisation and paves the way for new avenues of empirical research.</p
Parental use of distraction and portioning to reduce snack intake by children with avid eating behaviour:An experimental laboratory study
Get PDFIntroduction: Children's avid eating behaviour is characterised by frequent snacking and food responsiveness. Parents need evidence-based advice on specific feeding practices, such as distraction techniques and portioning, that can be used to reduce children's intake of high energy-dense snacks. This experimental laboratory study tested the effectiveness of these feeding practices. Methods: Parents and children (3–5 years; N = 129) who were identified as having an avid or typical eating profile were recruited and randomly allocated to one of three conditions. Following a standardised meal, children's energy intake (kcal) in the absence of hunger was assessed. While children had access to a snack buffet, parents were asked to use one of the following feeding practices: (1) Distract – using distraction techniques to delay children's snack intake; (2) Portion – allowing children to have snacks from pre-portioned pots; or (3) Control – allowing children to eat the type and number of snacks that their child wanted to. Results: Children in the distraction condition consumed significantly less energy from snacks (M = 54.44 kcal, SD = 73.30) compared to children in the portion (M = 103.89 kcal, SD = 91.33, p < .001) or control condition (M = 115.92 kcal, SD = 90.55, p < .001). Energy intake in the portion and control conditions was not significantly different (p > .05). Children with avid versus typical eating profiles did not differ significantly in energy intake (p > .05). Conclusion: Parental use of distraction techniques may be effective for reducing children's intake of high energy-dense snacks and could be recommended for use to support the development of children's healthy eating. Research to examine the effectiveness of distraction in real-world settings is now needed.</p
Access Repository Dashboard
Do you manage Edinburgh Research Explorer? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!